Birth histories collected during the first and second National Family Health Surveys (NFHS-1 and NFHS-2) show an unusually large proportion of male births in some population groups, which suggests that female fetuses are being aborted. Male births are particularly overrepresented in certain western and northern states, in families that already have daughters but no sons, and among women with a high level of education and media exposure. Analysis of women's ideal sex ratio (the ratio of ideal number of sons to ideal number of daughters) indicates that son preference is declining in almost all states and socioeconomic groups. Nevertheless, ideal sex ratios are still much higher than the biological norm, implying that considerable potential exists for further increases in levels of sex-selective abortion. The NFHS Subject Reports is a series summarizing secondary analysis of data from the 1992-93 National Family Health Survey (NFHS) in India. The NFHS collected information from nearly 90,000 Indian women on a range of demographic and health topics. Conducted under the auspices of the Indian Ministry of Health and Family Welfare, the survey provides national and state-level estimates of fertility, infant and child mortality, family planning practice, maternal and child health, and the utilization of services available to mothers and children. IIPS conducted the survey in cooperation with consulting organizations and 18 population research centers throughout India. The East-West Center and a U.S.-based consulting firm, Macro International, provided technical assistance, and the United States Agency for International Development (USAID) provided financial support. Printed copies are available from the East-West Center Research Program, Population and Health Studies. Single copies are available free by airmail and may be reproduced for educational use.